Reliable opening can end for reclosing can

ABSTRACT

A can end for a metal beverage can, the can end including a cap top, arranged in connection to a pull tab configured to remove the cap top from the can end along a pre-defined groove, to thereby create a drinking or pouring aperture; and a shut-off valve, configured to seal the drinking or pouring aperture after drinking or pouring. The cap top is configured to remain located, after the removal, on top of the shut-off valve; and the pre-defined groove includes a stop for arresting, in a pre-defined location of the pre-defined groove, propagation of a tear along the pre-defined groove during the removal, where the stop includes an abrupt change of direction or an endpoint of the pre-defined groove. The can may be configured for containing a carbonated drink.

FIELD OF THE INVENTION

The present invention relates to a container such as a can for a food product, especially a beverage, as well as a method of manufacturing the container or can. The container or can is especially suitable for carbonated beverages or drinks. The container or can can be provided with means for easily reclosing after the first opening.

BACKGROUND TO THE INVENTION

Metal beverage cans usually have a pull tab (working as a lever mechanism) to allow for the opening of the can along a pre-determined shallow groove or score. This design allows venting the excess pressure in the can when it is opened. As the tab is lifted, first a vent score is severed, allowing the gases in the can to be released, and then the aperture score is ruptured, which defines an aperture through which the contents of the beverage can may be dispensed. The groove has the shape of a non-closed loop, so that when pressure is applied by the lever to rip the metal along the groove, the metal tab that is ripped off remains attached to the top of the can, even when the lever is returned to its original position.

With existing cans, a permanent opening is formed by these manipulations, so that the contents of the can may be drunk, but on the other hand carbon dioxide may escape and spills may occur.

WO 2012/028694 A1 discloses a reclosing can for a food product, i.e. a can wherein the drinking or pouring aperture can be reclosed after the can is opened for the first time. WO 2014/124992 A1 discloses an intermediate element that may be used in the reclosing can of WO 2012/028694 A1.

US 2007/0131693 discloses an easy open can lid, having: a panel portion, which is formed of an approximate disc shape, and in which a flange portion for fixing a can trunk is formed integrally on an outer circumference; a score line, which is formed near the periphery of the panel portion along the outer circumference of the panel portion; an opening piece, which is defined by the score line; and an opening tab, which is fixed near the periphery of the opening piece. The score line is formed of an arcuate along periphery of the panel portion and both ends thereof are separated, and it comprises a connecting portion connecting the opening piece with the panel portion, which is formed between the both ends of the score line, and a strength incrementing portion, in which a rupture strength thereof increases gradually toward the end portion of the score line.

US 2015/0008221 discloses a can lid comprising a score line that branches off. In a panel of the can lid, a protrusion (nipple) is formed, which is flattened when a tab is secured to the panel and functions as a rivet. The protrusion is provided at a section of the panel which is surrounded by a first score line and which is located on a top part side relative to one end or the other end of the first score line. A second score line connected to a curved part of the first score line is provided in the panel.

WO 2014/200098 A1 and WO 2015/004965 A1, PCT applications of the same applicant as US 2015/0008221 and published in Japanese, disclose embodiments similar to those disclosed in US 2015/0008221.

SUMMARY OF THE INVENTION

The present invention provides an alternative container, e.g. a can for food products, especially beverages such as carbonated drinks. The container according to the present invention comprises improvements over the container disclosed in WO 2012/028694, “Reclosing can for food product”, which is included herein by reference, in its entirety. An advantage of embodiments of the present invention is their high reliability.

Preferred embodiments of a can end in accordance with the present invention include an improved embodiment of the pre-defined groove disclosed in WO 2012/028694.

One advantage of a container or can according to the invention is that it can easily be produced, and that it is suitable for mass production. In comparison with a traditional can, only the can end is different. Thus, a traditional production line of cans can be modified to produce the container or can, e.g. by replacing the production steps for the traditional can end by the production steps for the can end according to the invention; e.g. by adaptation of the tooling for the production line. The production steps and tooling for the can body and for attaching the can end to the can body can remain unchanged. A can end according to the invention may be made from a sheet of metal, having a given thickness; parts such as a pull tab are added. An advantage of a can end in accordance with the invention is that it requires only a small number of parts.

Another advantage is that embodiments of the invention can easily and successfully be applied to different types and sizes of can ends as known in the art, such as so-called SuperEnd (SE) can ends, Container Development Limited (CDL) can ends, etc. Embodiments of the invention can easily and successfully be applied to small can ends and to small can ends having large drinking apertures. All embodiments shown in the drawings were tested successfully. Yet another advantage is the very good pourability and drinkability of the contents of the can.

The present invention provides in one embodiment a can end for a metal beverage can, the can end comprising:

-   -   a cap top, arranged in connection to a pull tab configured to         remove the cap top from the can end along a pre-defined groove,         to thereby create a drinking or pouring aperture; and     -   a shut-off valve, configured to seal the drinking or pouring         aperture after drinking or pouring;

wherein the cap top is configured to remain located, after the removal, on top of the shut-off valve; and

wherein the pre-defined groove comprises means for arresting, in a pre-defined location of the pre-defined groove, propagation of a tear along the pre-defined groove during the removal,

wherein the means for arresting the propagation of the tear comprises an abrupt change of direction or an endpoint of the pre-defined groove.

The can may be configured for containing a carbonated drink.

The can end may comprise means for initiating the tear in an initiation location, wherein the can end is configured to propagate the tear in a first sense of rotation along the pre-defined groove from the initiation location to the pre-defined location and to propagate the tear in a second sense of rotation along the pre-defined groove from the initiation location, so as to remove the cap top from the can end, and wherein the second sense of rotation is opposite to the first sense of rotation.

The first sense of rotation may be a clockwise sense of rotation and the second sense of rotation a counter-clockwise sense of rotation, or the first sense of rotation may be a counter-clockwise sense of rotation and the second sense of rotation a clockwise sense of rotation

The can end may comprise means for preventing propagation of the tear outside of the pre-defined groove.

The means for preventing propagation of the tear outside of the pre-defined groove may comprise an elevation difference and/or an additional groove.

The cap top may comprise a second groove for decreasing an opening force during the removal of the cap top.

The can end may comprise a center point and a fixing device such as a rivet for attaching the pull tab to the can end, wherein the fixing device has a center and wherein the center point of the fixing device is at a nonzero distance from the center point of the can end.

The present invention also includes a metal beverage can optionally for carbonated drinks comprising a can body and a can end in accordance with the invention.

The present invention further includes a method for producing a can, embodiments of the method comprising producing a can end in accordance with the invention, producing a can body, and attaching the can end to the can body.

Embodiments of the present invention also include a method for opening a reclosing metal beverage can, optionally for carbonated drinks, the can comprising a can body and a can end, the method comprising:

-   -   actuating a pull tab of the can end, thereby initiating a tear         in a pre-defined groove of the can end, wherein the pre-defined         groove delimits a cap top;     -   arresting in a pre-defined location, at an abrupt change of         direction or an endpoint of the pre-defined groove, the tear         propagating in a first sense of rotation along the pre-defined         groove;     -   after the arresting the tear propagation, further actuating the         pull tab, thereby propagating the tear in a second sense of         rotation along the pre-defined groove, wherein the second sense         of rotation is opposite to the first sense of rotation;     -   still further actuating the pull tab, thereby still further         propagating the tear in a second sense of rotation along the         pre-defined groove, thereby removing the cap top from the can         end and thus creating a drinking or pouring aperture;     -   opening, by actuating the pull tab, a shut-off valve of the can         end, wherein the shut-off valve is configured to close and seal         the drinking or pouring aperture after drinking or pouring;

wherein the removed cap top remains located on top of the shut-off valve.

In an embodiment of the method, the first sense of rotation is a clockwise sense of rotation and the second sense of rotation is a counter-clockwise sense of rotation.

In another embodiment of the method, the first sense of rotation is a counter-clockwise sense of rotation and the second sense of rotation is a clockwise sense of rotation.

The method may comprise initiating and propagating a second tear along a second groove of the cap top, by actuating the pull tab.

The container or can will be described below especially when used for beverages, particularly carbonated drinks. It will be clear from the description however that the can may also be used for other food products, such as instant soup, instant coffee, oil, honey, sauces, dairy products such as milk or yoghurt, et cetera.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described, by way of example only, with reference to the accompanying drawings, wherein:

FIG. 1 shows a top view of an embodiment of a can end, based on a SuperEnd can end;

FIG. 2 shows a detailed view of a portion of the embodiment shown in FIG. 1, wherein the pull tab is omitted for clarity;

FIGS. 3a and 3b show 3D views of an embodiment of a can end including a shut-off valve; the can end is seen from the top in FIG. 3a and from the bottom in FIG. 3 b;

FIG. 4 shows a detailed view of a portion of another embodiment of a can end, wherein the pull tab is omitted;

FIG. 5 shows a detailed view of a portion of yet another embodiment of a can end, wherein the pull tab is omitted;

FIG. 6 shows a top view of an embodiment of a can end, based on a CDL can end;

FIG. 7 shows a detailed view of a portion of the embodiment shown in FIG. 6, wherein the pull tab is omitted for clarity;

FIGS. 8, 9, 10 and 11 each show a detailed view of a portion of other embodiments of a can end, wherein the pull tab is omitted for clarity; the embodiment shown in FIG. 11 is based on a so-called vented can end;

FIG. 12 shows a top view of an embodiment of a can end wherein the cap top is positioned asymmetrically;

FIG. 13 shows a detailed view of a portion of the embodiment shown in FIG. 12, wherein the pull tab is omitted for clarity;

FIG. 14 shows a top view of an embodiment of a can end wherein the cap top is slightly asymmetrical;

FIG. 15 shows a detailed view of a portion of the embodiment shown in FIG. 14, wherein the pull tab is omitted for clarity;

FIG. 16 shows a top view of an embodiment of a can end, based on a CDL can end with a circular drinking aperture;

FIG. 17 shows a detailed view of a portion of the embodiment shown in FIG. 16, wherein the pull tab is omitted for clarity;

FIG. 18 shows a top view of an embodiment of a can end, wherein the pull tab is positioned asymmetrically;

FIG. 19 shows a detailed view of a portion of the embodiment shown in FIG. 18, wherein the pull tab is omitted for clarity;

FIG. 20 shows a top view of an embodiment of a can end, wherein the can end includes an embodiment of an elevation difference;

FIG. 21 shows a detailed view of a portion of FIG. 20, wherein the pull tab is omitted for clarity;

FIG. 22 shows a detailed view of a portion of a top view of an embodiment of a can end, based on a can end with a so-called Love drinking aperture, and wherein the pull tab is omitted for clarity;

FIG. 23 shows a detailed view of a portion of a top view of an embodiment of a can end, based on a can end with a so-called Tulip drinking aperture, and wherein the pull tab is omitted for clarity;

FIG. 24 shows a detailed view of a portion of a top view of an embodiment of a can end, wherein the can end includes an embodiment of an additional groove, and wherein the pull tab is omitted for clarity;

FIG. 25 shows a detailed view of a portion of a top view of an embodiment of a can end, wherein the can end includes another embodiment of an additional groove, and wherein the pull tab is omitted for clarity;

FIG. 26 shows a detailed view of a portion of a top view of an embodiment of a can end, wherein the can end includes another embodiment of an elevation difference, and wherein the pull tab is omitted for clarity;

FIG. 27 shows a 3D view of a portion of the embodiment shown in FIG. 26.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other orientations than described or illustrated herein.

It is to be noticed that the term “comprising”, used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a device comprising means A and B” should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

FIGS. 1 and 2 show a first embodiment of a can end and FIGS. 3a and 3b illustrate another embodiment of a can end. Referring to FIG. 3a , the central part of the can end 2 has a tear panel or cap top 3, that can be torn off along a pre-formed shallow groove 9 or other form of mechanical weakness, by pulling at the pull tab 4, which works as a lever. Pull tab 4 is attached to can end 2 by a fixing device 10 such as a rivet. As disclosed in WO 2012/028694, “Reclosing can for food product” (mentioned hereinbefore), the cap top 3 is torn completely from the can end, i.e. removed from the can end, along the pre-defined groove 9, thus creating a drinking or pouring aperture. After tearing off the cap top 3, the cap top 3 remains located on top of a shut-off valve 6 (shown in FIG. 3b ), which is configured to seal the drinking or pouring aperture after drinking or pouring. The embodiment of the can end illustrated in FIG. 3b further comprises an intermediate element 80 to which the shut-off valve 6 is attached. For more details on possible embodiments of a reclosing can, we refer to WO 2012/028694 and WO 2014/124992. The can end shown in FIG. 3a further comprises a second groove 11, which is discussed further below, with reference to FIG. 6.

The embodiment of the pre-defined groove 9 shown in FIGS. 3a and 3b comprises means 21 for arresting propagation of a tear along pre-defined groove 9 during the removal of cap top 3, when the can is opened for the first time; this will now be discussed, referring to FIGS. 1 and 2.

It should be noted that in FIG. 1 the shown embodiment of the can end 2 comprises a first embossed ridge 16 and a second embossed ridge 17; both ridges protrude above the plane of the can end, as known in the art.

When opening the can for the first time, pull tab 4 is actuated and initiates a tear in pre-defined groove 9. The tear is initiated in a location near the position where the actuated pull tab touches the cap top, and then, when further actuating the pull tab, the tear propagates (referring to FIG. 2) from this location in a clockwise sense of rotation 42 along pre-defined groove 9 and in a counter-clockwise sense of rotation 41 along pre-defined groove 9 (clockwise and counter-clockwise when looking at the top view of the can end, i.e. when viewed from outside the can). However, groove 9 comprises an abrupt change of direction 21, so that the propagation of the tear in the counter-clockwise sense of rotation 41 along groove 9 is arrested, or stopped, in a pre-defined location 25, which in the embodiment of FIGS. 1 and 2 is the location of the abrupt change of direction 21 of groove 9. When further actuating the pull tab, the tear further propagates along groove 9 in the clockwise sense of rotation 42, until pre-defined location 25 is reached, resulting in removal of the cap top 3 from the can end 2.

That the tear propagates in this sequence is a result of the configuration of the can end, especially the position of the initiation location, i.e. the location where the actuated pull tab touches the cap top when the can is opened, with respect to the position of the pre-defined groove.

The abrupt change of direction 21 of pre-defined groove 9, illustrated in FIGS. 1 and 2 and also in FIG. 3a , is one embodiment of means for arresting propagation of the tear along the pre-defined groove 9 when opening the can for the first time. An advantage of arresting propagation of the tear in a pre-defined location 25 is reliability, because the process of opening the can is repeatable and is well under control, as was experimentally verified.

Another embodiment of means for arresting propagation of the tear along the pre-defined groove is an endpoint of the pre-defined groove, as discussed further below (the embodiment illustrated by FIG. 10).

Because of the abrupt change of direction 21 of the pre-defined groove 9, propagation of the tear is arrested in a pre-defined location 25. However, due to dimensional tolerances of the groove 9, due to material tolerances, due to differences in speed when actuating the pull tab, . . . the tear will not always be arrested exactly in identically the same location when opening a large number (for example one thousand) of cans. That the pre-defined groove 9 comprises an abrupt change of direction 21 means the following in the present document. In a top view of the can end, the groove 9 can be described as a mathematical curve. At the abrupt change of direction 21, this curve has either a discontinuous first derivative or its first derivative changes so fast that propagation of the tear is arrested in a portion of the pre-defined groove that comprises the pre-defined location and that has a curve length along the pre-defined groove that is less than 2 mm, preferably less than 1 mm.

FIG. 4 and FIG. 5 each show a detailed view of different embodiments of a can end (wherein the pull tab is omitted for clarity); in both embodiments the pre-defined groove comprises an abrupt change of direction 21 for arresting propagation of the tear in a pre-defined location 25, and the geometry of the abrupt change of direction 21 is different from the one illustrated by FIG. 2.

FIG. 6 shows an embodiment wherein the cap top 3 comprises a second groove 11. Because of the presence of the second groove 11, the force that is required to open the can when actuating pull tab 4 is decreased. Such a second groove is often used in traditional, non-reclosing cans with smaller drinking apertures, where the groove comprises sharper curves. The invention can also be applied to such can ends; different embodiments of a pre-defined groove 9 and a second groove 11 that were tested successfully are shown in FIGS. 7 to 11. In FIG. 8, pre-defined groove 9 is located at a very small distance from edge 15 of the central panel of the can end (compare FIG. 8 to FIG. 7).

FIG. 10 illustrates another embodiment of means for arresting propagation of the tear along the pre-defined groove, namely an endpoint 24 of the pre-defined groove 9.

FIG. 11 shows another embodiment of a can end with a second groove 11.

As discussed above, when opening the can for the first time, after the propagation of the tear is arrested, e.g. in the counter-clockwise sense of rotation, the tear propagates in the opposite sense of rotation, e.g. in the clockwise sense of rotation. Hence, this phase in the opening of the can is asymmetric. The force that has to be exerted on the pull tab can be decreased by positioning the cap top asymmetrically with respect to the pull tab. This is illustrated by FIGS. 12 and 13. FIG. 13 shows two axes 31 and 32 of can end 2; it is clear that points 9A and 9B on pre-defined groove 9 have an asymmetric position with respect to axis 31. The drinking aperture that is used by the customer, i.e. the portion between points 9A and 9B away from the pull tab, is symmetric, but it is positioned asymmetrically with respect to axis 31.

Another embodiment wherein the force on the pull tab is decreased is shown in FIGS. 14 and 15; in this embodiment, the drinking aperture that is used by the customer is slightly asymmetric. Of course, an asymmetric drinking aperture and an asymmetric position may be combined.

Instead of arresting the propagation of the tear in the counter-clockwise sense of rotation 41, as illustrated by FIG. 2, in another embodiment the propagation of the tear may be arrested in the clockwise sense of rotation, by positioning the means 21 for arresting the propagation of the tear in another position, i.e. at the other side of axis 31 when referring to FIG. 13.

FIGS. 16 and 17 show an embodiment of a can end, based on a CDL can end with a quasi-circular drinking aperture; the portion of the groove 9 between points 9C and 9D, positioned away from pull tab 4, is circular.

FIGS. 18 and 19 show an embodiment wherein the pull tab 4 is not attached to the center point of the can end. The can end has a center point, which is the intersection of its axis 31 and its axis 32. The position 10′ on can end 2 where the rivet 10 is attached, is at one side of axis 32 and the cap top 3 is (mainly) at the opposite side of axis 32, or, put otherwise, the rivet 10 has a center, where it is attached to the can end, and the center of the rivet 10 is at a nonzero distance from the center point of the can end. An advantage is that the drinking aperture can be very large, which is ideal for beer.

FIGS. 20 and 21 illustrate a first embodiment of means for preventing propagation of the tear outside of the pre-defined groove 9. It is not likely that the tear will propagate too far, but especially in the embodiment wherein the means for preventing propagation of the tear comprise an endpoint 24 of the pre-defined groove 9, as illustrated in FIG. 10, it is an advantage to have a safety measure against propagation of the tear outside of the pre-defined groove. In the embodiment of FIGS. 20 and 21, the means 27 for preventing propagation of the tear outside of the pre-defined groove 9 comprise a dome-shaped elevation difference 27 located near the abrupt change of direction 21 of the pre-defined groove and protruding above the plane of the can end. If, when opening the can, the tear would propagate further than the pre-defined location 25, it will be stopped by the elevation difference 27.

Instead of protruding above the plane of the can end, in another embodiment the elevation difference may lie below the plane of the can end.

FIG. 22 shows an embodiment of a can end, based on a can end with a so-called Love drinking aperture.

FIG. 23 shows an embodiment of a can end, based on a can end with a so-called Tulip drinking aperture.

FIG. 24 illustrates a second embodiment of means for preventing propagation of the tear outside of the pre-defined groove 9. In this embodiment, the means for preventing propagation of the tear outside of the pre-defined groove comprise an additional groove 28. In FIG. 24, the additional groove 28 is oriented perpendicularly to the direction of the pre-defined groove 9 in its endpoint 24 which is the means 24 for arresting propagation of the tear.

FIG. 25 illustrates a third embodiment of means for preventing propagation of the tear outside of the pre-defined groove 9, that is very similar to the one shown in FIG. 24. However, while in the embodiment of FIG. 24 the additional groove 28 passes through the endpoint 24 of the pre-defined groove, in the embodiment of FIG. 25 the additional groove 28 is positioned at a small distance, of e.g. 1 mm, from the abrupt change of direction 21.

FIGS. 26 and 27 illustrate a fourth embodiment of means 29 for preventing propagation of the tear outside of the pre-defined groove 9. In this embodiment, the means for preventing propagation of the tear outside of the pre-defined groove comprise an elevation difference 29 that has a shape similar to a wedge-like orange segment.

The present invention is not limited to the embodiments described above. Further, while advantages of embodiments of the present invention have been described above, not all embodiments need necessarily exhibit such advantages to fall within the scope of the present invention. The scope of the present invention is defined by the appended claims. 

1-15. (canceled)
 16. A can end for a metal beverage can, said can end comprising: a cap top, arranged in connection to a pull tab configured to remove said cap top from said can end along a pre-defined groove, to thereby create a drinking or pouring aperture; and a shut-off valve, configured to seal the drinking or pouring aperture after drinking or pouring; wherein said cap top is configured to remain located, after said removal, on top of said shut-off valve; and wherein said pre-defined groove comprises means for arresting, in a pre-defined location of said pre-defined groove, propagation of a tear along said pre-defined groove during said removal; wherein said means for arresting said propagation of said tear comprises an abrupt change of direction of said pre-defined groove or an endpoint of said pre-defined groove.
 17. The can end according to claim 16, further comprising means for initiating said tear in an initiation location, and wherein said can end is configured to propagate said tear in a first sense of rotation along said pre-defined groove from said initiation location to said pre-defined location and to propagate said tear in a second sense of rotation along said pre-defined groove from said initiation location, so as to remove said cap top from said can end, and wherein said second sense of rotation is opposite to said first sense of rotation.
 18. The can end according to claim 17 wherein said wherein said first sense of rotation is a clockwise sense of rotation and said second sense of rotation is a counter-clockwise sense of rotation, or wherein said first sense of rotation is a counter-clockwise sense of rotation and said second sense of rotation is a clockwise sense of rotation.
 19. The can end according to claim 16 further comprising means for preventing propagation of said tear outside of said pre-defined groove.
 20. The can end according to claim 19 wherein said means for preventing propagation of said tear outside of said pre-defined groove comprise an elevation difference.
 21. The can end according to claim 19 wherein said means for preventing propagation of said tear outside of said pre-defined groove comprise an additional groove.
 22. The can end according to claim 16 wherein said cap top comprises a second groove for decreasing an opening force during said removal of said cap top.
 23. The can end according to claim 16 further comprising a center point and a fixing device for attaching said pull tab to said can end, wherein said fixing device has a center and wherein said center of said fixing device is at a nonzero distance from said center point of said can end.
 24. The can end according to claim 16 wherein said metal beverage can is configured for containing a carbonated drink.
 25. A metal beverage can comprising a can body and a can end according to claim
 16. 26. The metal beverage can according to claim 25, configured for containing a carbonated drink.
 27. A method for producing the can according to claim 25, the method comprising the steps of: producing a can end; producing the can body; attaching the can end to the can body.
 28. A method for opening a reclosing metal beverage can, said can comprising a can body and a can end, the method comprising the steps of: actuating a pull tab of said can end, thereby initiating a tear in a pre-defined groove of said can end, wherein said pre-defined groove delimits a cap top; arresting in a pre-defined location, at an abrupt change of direction or an endpoint of said pre-defined groove, said tear propagating in a first sense of rotation along said pre-defined groove; after said arresting said tear propagation, further actuating said pull tab, thereby propagating said tear in a second sense of rotation along said pre-defined groove, wherein said second sense of rotation is opposite to said first sense of rotation; still further actuating said pull tab, thereby still further propagating said tear in said second sense of rotation along said pre-defined groove, thereby removing said cap top from said can end and thus creating a drinking or pouring aperture; opening, by said actuating said pull tab, a shut-off valve that is configured to close and seal said drinking or pouring aperture after drinking or pouring; wherein said removed cap top remains located on top of said shut-off valve.
 29. The method according to claim 28 wherein said first sense of rotation is a clockwise sense of rotation and said second sense of rotation is a counter-clockwise sense of rotation, or wherein said first sense of rotation is a counter-clockwise sense of rotation and said second sense of rotation is a clockwise sense of rotation.
 30. The method according to claim 28 further comprising initiating and propagating a second tear along a second groove of said cap top, by said actuating said pull tab. 